Remove redundant binding of _PyramidDepthTexture

We used to bind it in HDRenderPipeline.RenderPyramidDepth and BufferPyramid.RenderDepthPyramid.  BufferPyramid seems to own the binding, so remove the HDRP binding.

ScriptableRenderPipeline/HDRenderPipeline/HDRP/HDRenderPipeline.cs

 
             Vector2 pyramidScale = m_BufferPyramid.GetPyramidToScreenScale(hdCamera);
             PushFullScreenDebugTextureMip(cmd, m_BufferPyramid.depthPyramid, m_BufferPyramid.GetPyramidLodCount(hdCamera), new Vector4(pyramidScale.x, pyramidScale.y, 0.0f, 0.0f), hdCamera, debugMode);
-
-            cmd.SetGlobalTexture(HDShaderIDs._PyramidDepthTexture, m_BufferPyramid.depthPyramid);
         }
 
         void RenderPostProcess(HDCamera hdcamera, CommandBuffer cmd, PostProcessLayer layer)